Manufacture of rubber coated footwear



`- R. v. CARBERRY l 2,308,586

MANUFACTURE OF RUBBER COATED FOOTWEAR y"Filed April 28, 1941 mentes Jee 19, 1943 asoasss mancuernas or nonnen coA'rEn roorwaan Robert Vincent'Cai-berry, DouglastomN. Y., as-

signor to J. C. Penney Company, New N. Y., a corporation of Delaware York,

Application April 28, 1941, Serial'No. 390,8y

3 Claims. (Ci. 12=142) This invention relates to manufacture of rubber coated footwear. and it comprises a sock or stocking having a flexible, outer rubber coating `extending over its sole and -upwardly for a short distance only over toe. instep and heel, said coating being suiliciently thick to be substantially impervious to water and to provide a durable outer wearing surface, the inner surface of the sock or stocking, being substantially free from rubber, an uncoated insole being sometimes provided inside of the article, said article being particularly useful for wear at bathing beaches and the like. Myl invention also includes a method of manufacturing said footwear which comprises fitting a sock or stocking tightly over a form or last, securing over the upper portion of the outside of the sock a close-fitting metal shield serving to delineate the upper desired limit of the rubber coating, then dipping the sock, form and shield into a bath containing a dispersion of rubber for a distance sufilcient to produce the desired rubber coating on the sole of said sock and extending for a short distance over toe. instep and heel, the dipping operation being advantageously conducted under conditions substantially preventing the penetration of the rubber into the interior of said sock, drying the resulting coating and, if desired, vulcanizing the same; all as more fully hereinafter set forth and as claimed.

. 'While rubber footwear of various types andforms has been proposed for use at bathing beaches, bath houses and the like, most of thel rubber articles which have come into use for this purpose have been mere modifications of the usual rubber overshoes or sandals. Most of these have been of low form and loose tting. Footwear of this type are unsuited for use in the playing of games which are becoming more popular daily at the beaches, since they slip oif too readily.

. Most footwear of this type has been manufactured in such fashion that the foot is in direct contact with a layer of rubber or rubbereimpregnated cloth. In the coating operations described in the art. for example, there has been the feet vto sweat which c mi a ci feel- .ing and they prevent ventilation and the radiation of heat from the feet.

I have discovered a very simple method-of proe ber coating which forms a sole and extendsfor a short distance upwardly along the edges or sides of the foot. the inner surface 'of the sock or 4stocking being substantially free from this coating. The upper part of sock or stocking is, of course, close fitting and this prevents the article frombeing thrown oi! while the wearer isrunning, for example. The innersurface of the article is comfortable owing to the substantial absence ofv rubber and, if. desired, the comfort maybe increased by providing an insole which is free from rubber. While full length stockings may be coated in this manner, I prefer to employ socks having a length about that of the popular "whoopie socks." vThe upper edge may be rolled down by the wearer to any height l desired. This upper edge may be provided with an elastic if desired adapted to prevent the sock from slipping down.

- The article Adescribed reproduced by e. simple dipping operation. The sock to be coated t.; first .stretched tightly over a form of wood or the like,

` coating is to extend and being provided with means, such as a stop or brace to hold the same in correct position. This assembly is then dipped into a dispersion or solution of rubber to a depth usually somewhat above the metal shield. If it is desired to produce a' coating which is thicker than that obtainable by a single dip. the coat is dried for a short time and a second dip is made, the rubber being built up until it is of the desired thickness. l

The assembly is then dred or the shield may be'removed before the drying operation, if deaired. The upper edge of the coating may be smoothed, if necessary, by ironing it with a hot linstrument. Drying may be conducted at ordinary or slightly elevated temperatures. The coated sock may then be removed from the form. If rubber latex is used as the dipping bath, it is usually vnot -f ventional rubber latex. that is,'an aqueous dispersion of rubber having a concentration of about 60 per cent solids and containingv ammonia as a preservative, although itis possible to employl one ofthe usual rubber'cements, formed' by 'dis 4 persing rubber in organic solvents. Insifoadofu` 1 having an outer rub- 55 rubber it is possible to employ. balatafguttaf' f to mlcanize the rubber I coating although this can be accomplished if del sired.

` The coatingbath preferably contains the conpercha or synthetic rubber. The term "rubber as used in the description and claims is intended to cover these equivalent materials.

It it is desired to prevent penetration of the rubber into the interior of the sock, this can be accomplished in various ways. If the sock is closeLv knit, it is possible to employ a rubber dispersion of suillciently high viscosity such that its surface tension prevents substantial penetration into the pores of the sock. It is also possible .to employ anti-wetting agents to prevent this penetration. If rubber latex is used in the coating bath, any of the so-calledrwaterrepellent agents can be employed, such aszinc stearate, calcium stearate etc. These -can be dusted into the inside of the sock prior to the dipping operation or a solution of water-repellent agent can be sprayed on the socks when turned inside out, for example. Sulfur has sumcient water-repellent properties to produce the desired effect and this can be applied either in powder form or in the form of a solution in an organic solvent. by dipping or spraying. Satisfactory results are also obtained by spraying the inside of the socks with a volatile oil serving as a water repellent agent. If a dispersion of rubber in an oily medium is employed, it is possible to use water as an anti-wetting agent for example. An anti-wetting agent can be applied to the shield, if desired, and this tends to prevent penetration of the rubber underneath the shield and also the deposit of a rubber coating on the shield. The application of an anti-wetting coating on the wooden form also is of assistance in preventing penetration of .the rubber into the interior of the sock. The anti-wetting agent employed should, of course, be nonpoisonous.

Instead of dipping the sock into the rubber dispersion it is possible to apply the coating to the sock by brushing or a spraying operation. It is also possible to employ electro-deposition methods to apply the desired rubber coating on the socks.

The rubber dispersion may contain various illlers, pigments and reinforcing agents, if desired, such as Whiting, clay, lithopone, lamp black and the like. If it is desired to vulcanize the coating, it is also possible to include vulcanizing and accelerating agents in the dispersion. -A dispersion of sulfur in latex can be used as a coating bath, for example.

Vulcanization of the rubber coating may be accomplished in various ways. If al vulcanizing agent is dispersed in the coating bath, this is distributedin the rubber coating and it is only necessary to heat the coating to vulcanizing temperatures after drying it. If it is desired to produce a smooth rubber surface or to decorate the surface in any way, the coated sock can be compressed between heated` dies during the vulcanization in known manner.y A decorated surface can also be produced by embossing the rubber coating by means o! rollers prior to vulcanisation. o

2 per cent solution of sulfur chloride in carbon disulfide.

My invention can be described in more detail by reference to the accompanying drawing which shows, more or less diagrammatically. several embodiments of my invention. In this showing,

Fig. 1 represents a perspective view of a sock and shield mounted on a wooden form ready for dipping, the showing being broken away in part in order'to show the disposal of the parts, while Fig. 2 is an enlarged partial cross section through a finished sock provided with my rubber coating.

The figures in the drawing are supplied with descriptive legends, which are believed to be self explanatory, as well as with reference numerals. Referring to Fig. 1, the sock I is shown stretched over the wooden form 2, the latter being supplied with a handle 3 which may be screwed into the form, as shown at I. The metal shield is shown at 6. This shield is provided with means l. which may take the form of simple braces or stops to holdvthe shield in correct position during .the dipping operation. The braces shown are pressed firmly against the top of the sock and prevent the shield from being pressed too far over the sock. The upper edge of the sock can be provided with an elastic, if desired, as shown at l.

In Fig. 2 the rubber coating is shown at l. It will be noted that the inside of the sock is free from rubber. An insole I is shown in this gure although this may be omitted, if desired, owing to the fact that the inside oi the sock is smooth and substantially free from rubber.

While I have described what I consider to be the best embodiments, of this invention, it is obvious that various modiilcations can be made in the specific procedures which have been described without departing from the purview of this invention. The coating of this invention' can, of course, be varied ln height and may extend entirely across the iorepart of the foot, if

desired. It is usually better, however, to provide a coating which extends upwardly not substantially over one inch since this is sufllcient to prevent the sifting of sand through the sock and also the access of moisture. The sock is then lighter and cooler-more ventilation is provided. It should be noted that, on account of the substantial absence of rubber in the pores of the sock, the wall of the sock. even where coated with rubber, is ventilated owing to the open pores extending along the sock wall. Various foot forms and shields may be employed which may be constructed of metal, plastic or other materials. And it is possible to vary the composition of the coating bath widely. Itis possible to employ this invention in the coating of all types of porous fabrics and cloth materials, whether woven or knit, etc. Knit cotton socks are `probably the most serviceable of the materials which can be employed. Other modications of this 5 invention whichfall within the scope oi' the following clalms will be immediately evident to those skilled in this art.

What I claim is:

.1. In the manufacture oi rubber coated footweanthe process which comprises impregnating the inner surface only ot a sock of porous material with a water-repellent agent, fitting the sock over a foot form, placing over the upper portion or the sock' a closely-stung einem adapted to delineate the upper limit oi' a rubber coating 2,808,588 and leaving the sole and a portion of the sides o! the sock uncovered, then dipping the uncovered portion of said sock into a coating bath containing rubber latex, whereby a rubber coating is produced which covers the sole and a portion 'of the sides of the sock without substantially penetrating the pores of said sock, and then drying said coating.

2. the manufacture oi' rubber coated footwear, the process which comprises impregnating the inner surface only of a sock o! porous material with a water-repellent agent, coating the outside of a foot form with said water-repellent agent, fitting the sock over said foot form, placing over the upper portion of the sock a closelystung shield adapted to delineate the upper limit of a rubber coating and leaving the sole and a portion oi' the sides of the sock uncovered. then dipping the uncovered portion oi said sock into a coating bath containing rubber latex. whereby a rubber coating is produced which covers the sole and a portion of the sides of the sock without substantially penetrating the pores of said sock, and then drying said coating.

3. In the manufacture oi' rubber coated footwear, the process which comprises ixnpregnating the inner surface only of a sock of porous material with a water-repellent agent, coating the outside of a foot form with said water-repellent agent, also coating with said agent a closely fitting shield adapted to delineate the upper limit of a rubber coating, tting the sock over said foot form, placing said shield over the upper portion of'the sock, leaving the sole and a portion of the sides 'of the sock uncovered, then dipping the uncovered portion of said sock into a coating bath containing rubber latex, whereby ya rubber coating is produced which covers the sole and a portion of the sides of the sock without substantially penetrating the pores of said sock and without penetrating beneath said shield, and then drying said coating.

ROBERT VINCENT CARBERRY. 

